1. Field of the Invention
The present invention relates to a network management method, program and apparatus for managing an interconnecting network where a plurality of computers are interconnected by switch apparatuses to construct a parallel computer system, and particularly to a network management method, program and apparatus for an interconnecting network where a plurality of physical lines connecting switch apparatuses are bundled to assume one logical line, thereby enhancing a line transmission speed (band).
2. Description of the Related Arts
Conventionally, there has been constructed a parallel computer system such as cluster system through an interconnecting network (interconnect) for mutually connecting many computers through switch apparatuses having a line transmission speed of giga-bit order. When the number of computers for constructing the parallel computer system is large, in many cases, many switch apparatuses are used for the interconnecting network for connecting each computer (interconnect) and a plurality of lines are provided between the switch apparatuses to logically assume one line so as not to decrease the line transmission speed (bit rate of bps) between the switch apparatuses, thereby enhancing the line transmission speed. A method for bundling a plurality of physical lines to logically assume one high-speed line in this manner is called trunking (JP2002-232427). Since the line transmission speed defined by bit rate (bps) increases along with spread in a band of the line, the line transmission speed is customarily represented as the band of line, and, for example, the expression that the band of line increases (expands) means that the line transmission speed increases. In the parallel computer system, many power saving methods are applied for elements such as processor, memory and hard disk drive, etc. constituting an individual computer. On the other hand, a switch apparatus which constitutes a network connecting a plurality of computers is always in a powered state and operates in a state where data transmission at a maximum data transmission speed determined by the line transmission speed can be always provided. Further, as a method for performing power saving of the switch apparatuses constituting a network, there has been proposed a method for monitoring packet incoming to perform disabling and enabling of port function units (JP2001-320415).
However, in the conventional interconnecting network where there is trunking in which a plurality of physical lines are bundled to assume one logical line, in many cases, the maximum data transmission speed corresponding to the line transmission speed is required in a short time, and communication at a data transmission speed lower than the line transmission speed is made for most time so that an excessive line communication speed is provided for the necessary data transmission speed. For example, in JP2002-232427, although a plurality of physical lines are provided between switches to enhance the line transmission speed, even in the case of less communication, the less communication is evenly divided into the plurality of physical lines, and consequently the data transmission speed is lowered for the line transmission speed of the physical lines, which is wasteful, and nevertheless all the port units are operating so that power saving cannot be expected. In a method for monitoring packet incoming to perform disabling and enabling of the port units in JP2001-320415, since the lines are completely shut off logically when disabling the port units, there is a problem that the network form is changed to cause large adverse effect on the system.